VLT
®
2800 Series
The jog ramp time starts if a jog-signal is given via
the LCP control panel, one of the digital inputs
or the serial communication port.
Description of choice:
Set the required ramp time.
212 Quick-stop ramp-down time
(Q STOP RAMP TIME)
Value:
0.02 - 3600.00 sec.
✭
3.00 sec (VLT 2803-2875)
10.00 sec (VLT 2880-2882)
Function:
The quick-stop ramp-down time is the deceleration
time from the rated motor frequency to 0 Hz, provided
no overvoltage arises in the inverter because of
generating operation of the motor, or if the generated
current exceeds the current limit in parameter 221
Current limit I
LIM
. Quick-stop is activated via one of
the digital inputs or the serial communication.
Description of choice:
Set the required ramp-down time.
213 Jog frequency
(JOG FREQUENCY)
Value:
0.0 - Par. 202 Output frequency high limit, f
MAX
✭
10.0 Hz
Function:
Jog frequency f
JOG
means a fixed output frequency
that the frequency converter supplies to the motor
when the Jog function is activated. Jog can be
activated via the digital inputs, serial communication
or via the LCP control panel, on the condition that
this is active in parameter 015
Local jog
.
Description of choice:
Set the required frequency.
■
Reference function
The example shows how the resulting reference is
calculated when
Preset references
is used together
with
Sum
and
Relative
in parameter 214
Reference
function
. The formula for the calculation of the
resulting reference can be seen in the section
entitled
All about the VLT 2800
. See also the
drawing in
Handling of references
.
The following parameters are preset:
Par. 204
Minimum reference
10 Hz
Par. 205
Maximum reference
50 Hz
Par. 215
Preset reference
15 %
Par. 308
Term. 53, Analogue input
Reference
Par. 309
Term. 53, min. scaling
0 V
Par. 310
Term. 53, max. scaling
10 V
When parameter 214
Reference function
is set to
Sum
[0] one of the preset
Preset references
(par. 215-218) is
added to the external references as a percentage of the
reference range. If terminal 53 is applied an analogue
input voltage of 4 Volt will be the resulting reference:
Par. 214
Reference function
= Sum [0]:
Par. 204
Minimum reference
10.0 Hz
Reference contribution at 4 Volt
16.0 Hz
Par. 215
Preset reference
6.0 Hz
Resulting reference
32.0 Hz
When parameter 214
Reference function
is set
to
Relative
[1] the defined Preset references (par.
215-218) are added as a percentage of the total
of the present external references. If terminal
53 is applied to an analogue input voltage of 4
Volt the resulting reference will be:
Par. 214
Reference function
= Relative [1]:
Par. 204
Minimum reference
10.0 Hz
Reference effect at 4 Volt
16.0 Hz
Par. 215
Preset reference
2.4 Hz
Resulting reference
28.4 Hz
The graph shows the resulting reference in relation to
the external reference, which varies from 0-10 Volt.
Parameter 214
Reference function
is programmed
to
Sum
[0] and
Relative
[1] respectively. Also
shown is a graph in which parameter 215
Preset
reference 1
is programmed to 0 %.
✭
= factory setting. () = display text [] = value for use in communication via serial communication port
MG.28.E9.02 - VLT is a registered Danfoss trademark
82
